Draw and explain the structure of a web browser.

Generally, a browser is referred to as an application that provides access to a Web server. Depending on the implementation, browser capabilities and thus structures vary. A Web browser, at a minimum, consists of an Hypertext Markup Language (HTML) interpreter and HTTP client that is used to retrieve HTML Web pages. Besides this basic requirement, many browsers also support FTP, NNTP, e-mail (POP and SMTP clients), among other features, with an easy-to-manage graphical interface. Fig.5. illustrates a basic Web browser structure.

                                                       Fig. 5. Structure of a web browser
As with many other Internet facilities, the Web uses a client/server processing model. The Web browser is the client component. Examples of Web browsers include Mozilla Firefox, Netscape Navigator, and Microsoft Internet Explorer® Web browsers are responsible for formatting and displaying information, interacting with the user, and invoking external functions, such as Telnet, or external viewers for data types that Web browsers do not directly support. Web browsers have become the “universal client” for the GUI workstation environment, in much the same way that the ability to emulate popular terminals such as the DEC VT100 or IBM 3270 allows connectivity and access to character-based applications on a wide variety of computers. Web browsers are widely available for all popular GUI workstation platforms and are inexpensive.